WASHINGTON — U.S. household net worth jumped $1.3 trillion in the spring, fueled by gains in home and stock values.The Federal Reserve said Wednesday that net worth rose to $74.8 trillion in the April-June quarter, up 1.8 percent from the first quarter. Home prices and stock markets have risen further since then, suggesting that Americans' net worth is now even higher.The gains in wealth haven't been evenly distributed. Home ownership has declined since the recession, particularly among lower-income Americans. And the wealthiest 10 percent of households own about 80 percent of stocks.Americans' wealth bottomed at $57.2 trillion in 2008 during the Great Recession. It's since risen $17.6 trillion.Household wealth, or net worth, reflects the value of assets like homes, stocks and bank accounts minus debts like mortgages and credit cards.Greater net worth can boost consumers' willingness and ability to spend. That could accelerate economic growth. Some economists say higher household wealth enabled Americans to spend more this year despite higher Social Security taxes and higher income taxes on wealthier Americans that took effect at the start of the year.Home values rose $525 billion in the April-June quarter, stock and mutual fund portfolios $300 billion.Consumers took on slightly more debt last quarter, mostly in the form of auto and student loans. Credit card debt rose slightly, too.On Wednesday, the Fed revised up its previous data on household wealth to reflect changes in the government's accounting of pension promises. The government now counts benefits that are promised by pension plans as an asset. This change added about $3 trillion in wealth to previously reported figures.